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Is it possible for a lunar eclipse to occur during the night and then be followed by a solar eclipse the next day? Could these two events happen consecutively, and if so, how rare is this phenomenon?

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  • $\begingroup$ At least 2 and at most 3 eclipses will occur during every eclipse season. Also see eclipsewise.com/solar/SEhelp/SEperiodicity.html & eclipsewise.com/lunar/LEhelp/LEperiodicity.html $\endgroup$
    – PM 2Ring
    Mar 24 at 7:26
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    $\begingroup$ Not without moving the Moon significantly closer to the Earth... $\endgroup$ Mar 25 at 14:23
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    $\begingroup$ @CarlWitthoft 1) that's not a close reason, 2) since this question has already generated two thoughtful and well-received answers, the question should not be closed. Closing prevents answer - the only thing it does is prevent anyone from creating another answer post. If you want to respond to lack of research, the down vote button is the correct action, not answer-blocking. Also keep in mind that we should always strive to be helpful and courteous, not condescending, and that goes double for new users. $\endgroup$
    – uhoh
    Mar 26 at 1:36
  • $\begingroup$ Well, it should be. Otherwise, SE will just continue its slide into the muck of irrelevance. $\endgroup$ Mar 26 at 15:14
  • $\begingroup$ What did your almanacs or ephemerises say about that? $\endgroup$ Mar 31 at 17:05

3 Answers 3

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No.

A lunar eclipse occurs when the moon is on the opposite side of the Earth as the sun.

A solar eclipse occurs when the moon is on the same side of the Earth as the sun. And it takes the moon 14 days to go 180 degrees around the Earth.

So it is common that there is a lunar eclipse 14 days before or after a solar eclipse. (for example, on Mon, 25 Mar 2024 there is a penumberal lunar eclipse, 14 days before the solar eclipse of April 8th.

It is impossible for a lunar eclipse to be followed the next day by a solar eclipse.

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    $\begingroup$ Another way to put this is that solar eclipses always happen during a new moon, while lunar eclipses are always during a full moon. And these alternate every 2 weeks. $\endgroup$
    – Barmar
    Mar 25 at 14:39
  • $\begingroup$ In other news, Josephus was bad at astronomy. $\endgroup$
    – Joshua
    Mar 25 at 17:30
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Yes… if you're on Mars.

Earth's Moon is far enough from Earth that its synodic orbital period (i.e. the time between two full moons or two new moons) is about 29.5 Earth days. The time between a full moon and a new moon is half of that, or just under 15 days. Since a lunar eclipse can only occur during a full moon, and a solar eclipse can only occur during a new moon, they can never happen less than two weeks apart.


However, the inner moon of Mars, Phobos, is much smaller than Earth's moon but also orbits much closer to Mars — so close, in fact, that it completes a (sidereal) orbit around Mars in only 7 hours and 39 minutes, or less than one third of a single Mars day (which, at 24 hours and 39 minutes, is slightly longer than an Earth day).

While Phobos is not quite big enough (or close enough to Mars) to fully eclipse the Sun, it still covers a decent portion of the solar disc during transit, so I at least would consider that to qualify as a (partial or annular) solar eclipse.

The orbit of Phobos is almost exactly aligned with the equator of Mars. During Martian equinox, an observer near the equator would be able to see Phobos passing in front of the Sun, eclipsing it. Meanwhile, about 3 hours and 50 minutes later Phobos will pass through the shadow of Mars, itself becoming fully eclipsed. With the right timing, a single observed on Mars could be able to observe both events. If not, another Phobos eclipse should occur one orbit later, or about 11.5 hours after the solar eclipse.

And of course the same math works in the other direction as well, so there will be Phobos eclipses 3 hours 50 minutes and 11 hours 30 minutes before each solar eclipse by Phobos, too. (In fact, according to Wikipedia there will typically be a series of around half a dozen successive solar eclipses and Phobos eclipses each.)


Actually, a similar sequence of eclipses should be observable with the second moon of Mars, Deimos, as well.

While Deimos orbits slightly outside the synchronous orbit of Mars, and thus takes more than one Mars day to complete an orbit, its orbital period of 30.3 hours is only slightly longer than the rotation period of Mars. As a consequence, viewed from the surface of Mars, Deimos moves very slowly across the sky, setting almost 60 hours (or almost 2 and a half days, or about two complete Deimos orbits!) after rising. That's plenty of time for Deimos to pass both in front of the Sun (eclipsing it) and through the shadow of Mars (being eclipsed) about 15 hours apart.

However, Deimos being both smaller and further away from Mars than Phobos, a solar transit of Deimos looks a lot less impressive than a Phobos transit. It's more like just a small black spot moving across the solar disk than anything we'd normally consider an eclipse.

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  • $\begingroup$ IN general usage, any object too small to fully block the eclipsed item under any alignment conditrion is considered to be executing a "transit" and not a "partial eclipse" $\endgroup$ Mar 25 at 23:02
  • $\begingroup$ Though OP tagged the question with the-moon, restricting the answers to refer to Earth's "natural" satellite. lunar-eclipse also restricts answers. $\endgroup$ Mar 26 at 13:51
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    $\begingroup$ I realise this is a serious scientific community, and I further realise that for reasons in other comments this answer is out of scope, however after years of reading posts here and not getting involved, I have just registered with this community so I can say that in spite of all the above, I learned something new and hugely interesting to me from this entirely out of scope answer. Also I would never have watched the video of the Phobos transit without it. Thank you! $\endgroup$
    – ThaRobster
    Mar 26 at 16:07
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YES.

If you're on the moon.

A moon day is 28 Earth days long. From the moon, in the middle of the night, you can see the moon's shadow cross the Earth, then the next moon day (14 Earth days later) you can see the Earth block out the sun.

It all depends on what you're willing to call an eclipse. Like most naming in astronomy, an eclipse was first defined only as seen from Earth. The concept of standing on another celestial body and looking up at the sky is very recent in human history, and language has not caught up.

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    $\begingroup$ Funny answer, but probably a dodgy use of terminology. I'm not sure you can have a lunar eclipse on the Moon, just like you can't have a terrestrial eclipse on the Earth. Surely a Sun-Earth-Moon alignment would, from the point of view of the Moon, be a solar eclipse, while Sun-Moon-Earth would be a terrestrial eclipse. $\endgroup$ Mar 24 at 22:28
  • $\begingroup$ A terrestrial eclipse would require something planet-sized to come between the Moon and the Earth, wouldn't it? Sun-Moon-Earth, to an observer on the Moon, is just lunar day on the far side and lunar night on the near side, I think. $\endgroup$
    – zwol
    Mar 25 at 2:06
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    $\begingroup$ @zwol No, it wouldn't, it just requires the entire Earth to be covered by the shadow of the Moon (which can't happen). $\endgroup$
    – gerrit
    Mar 25 at 7:26
  • $\begingroup$ @gerrit Do you not consider an annular eclipse to be an eclipse? If the Moon's shadow falls entirely on the Earth, such that only a ring of Earth is visible from a certain point of the Moon, I'd call that an annular terrestrial eclipse viewed from the Moon. But this is just semantics at this point. $\endgroup$ Mar 25 at 9:55
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    $\begingroup$ From the moon, the earth has about 4x the angular diameter of the sun. There's no firm definition of what separates an eclipse from an occultation, but "eclipse" is generally reserved for bodies of similar angular size. The earth's angular area is an order of magnitude larger than the sun's from the moon; one could say it simply occludes the sun rather than eclipsing it. $\endgroup$ Mar 25 at 12:53

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